Seasonal effects on the aerobic bacterial and fungal conjunctival flora of normal thoroughbred brood mares in Florida

Abstract

There were no significant differences between the number or type of organisms cultured during the sampling seasons in normal Florida horses. A large range of normal bacterial and fungal flora were isolated from these horses. The number of bacteria and fungi isolated are not uniform across seasons. The likelihood of detecting an organism depends on the horses' age.

Bacterial culture and antibiotic sensitivity from the ocular conjunctiva of horses

“…is a gram-negative bacillus, considered as one of the most virulent pathogens of the cornea, with a prevalence between 6 and 14% among the microorganisms identified in corneal ulcers of horses (SAUER et al, 2003;KELLER & HENDRIX, 2005;WADA et al, 2010;WADA et al, 2010). As expected, this genus was not isolated in the present study; although, it was previously identified in the eyes of horses without ophthalmic problems (ANDREW et al, 2003;VIDAL et al, 2010;JOHNS et al, 2011).…”

“…Such discrepancy has been attributed to the ambient temperature and management to which the animal is subjected (PISANI et al, 1997;JOHNS et al, 2011); although, some authors have not identified any significant difference in the number or types of microorganisms isolated during different seasons of the year (ANDREW et al, 2003). Of the 200 samples collected in the present study, 131 (65.5%) showed bacterial growth (Table 1).…”

“…This was also reported in the present study, where these genera represented 43 and 13% of the total strains isolated, respectively (Table 1). ANDREW et al (2003), however, identified Corynebacterium as the most important genus in the ocular conjunctiva of healthy horses, followed by Staphylococcus and Bacillus. In the present study, Corynebacterium sp.…”

“…In the present study, the search for MRS strains was not performed, but according to the researches published so far, healthy horses that have not undergone any recent surgical procedures and that are not under antibiotic treatment, are not predisposed to MRS infections. ANDREW et al (2003) identified Rhodococcus equi in the horse conjunctiva in five samples, representing only 0.2% of the total isolates. In our research, this bacterium was reported in 27 samples, where it accounted for 13% of the isolates identified.…”

“…In different animal species, including horses (ANDREW et al, 2003;JOHNS et al, 2011), mules (TAMARZADEH & ARAGHI-SOOREH, 2014), donkeys (FOTI et al, 2013), sheep (BONELLI et al, 2014), dogs (PRADO et al, 2005) and rabbits (ORIÁ et al, 2014). Bacterial population often isolated from healthy eyes is composed of gram-positive bacteria, although strains of methicillin-resistant to Staphylococcus (MRS) and gran negative strains, have also been identified (SANTOS et al, 2009;JOHNS et al, 2011;WILLCOX, 2013;MOUNEY et al, 2013).…”